An example of a flow control device of this type includes a device equipped with a flush valve device disclosed in JP 07-189311 A, which was previously filed by the applicant of the present invention.
In particular, the flow control device includes a main control valve arranged in a path leading from an inlet to an outlet, a pressure chamber positioned behind the main control valve and has therein a spring for biasing the main control valve toward a valve seat while keeping a balance with respect to the inlet side, a pilot valve for allowing the main control valve to open by releasing pressure in the pressure chamber, and a flowmeter unit 81 for measuring a flow rate of water flowing from the inlet to the outlet. Based on an output of the flowmeter unit, a valve opening of the pilot valve is automatically controlled and an appropriate amount of the water is caused to flow through the outlet to be discharged to a stool or the like.
In recent years, measures for environmental issues are taken in various fields, so an improvement in an environmental issue of the flush valve device of this type is also in demand.
In particular, according to an intensive study of the inventors of the present invention, in a field of the flush valve device of the automatic water stop type having a water-saving effect higher than a manual water stop valve, there was found a point to be improved about a method of supplying electricity to a control system of the flush valve device.
Further, in the flush valve device of the automatic water stop type, presence/absence of discharge and a period of time for discharge are managed by performing various controls based on a sensor output. Therefore, the device tends to be complicated in structure as compared to the manual water stop valve. In addition, in mounting the device to an installation place, tasks for leading an external power thereinto, etc. are required. Besides, the flush valve device of this type may obtain the high water-saving effect, so there is a fear of the device being stolen. Therefore, improvements in maintenance/management after construction have also been required.
On the other hand, in facilities such as public lavatories where a plurality of flow control devices of this type are installed, it is possible to grasp a used amount of water with reference to a water meter provided to a water supply main pipe. However, the water meter indicates a flow rate in the whole facility including both stools and wash stands, so it was difficult to individually grasp the flow rate of the water consumed in each of the stools and the wash stands.
Among others, in the flow rate control valve composed of the flush valve device of the automatic water stop type, the flow rate of the water to be discharged is managed through an automatic control of the pilot valve based on the sensor output. Therefore, it is important to accurately grasp the flow rate of water in each of the flow rate control valve for effectively performing the maintenance/management after the construction.
Further, the flow rate of the water involved in discharge is information useful for the management of the facility. By accurately grasping the flow rate, it is possible to definitely grasp the water-saving effectiveness or the like involved in, for example, adoption of the flush valve device of the automatic water stop type.
The present invention has been made in view of such the technical background. It is an object of the present invention to provide a flow control device having a power-saving effect in addition to the water-saving effect. Further, it is another object of the present invention to provide the flow control device which also facilitates construction, maintenance, and management thereof.